咽拭子及痰液标本肺炎支原体培养对支原体肺炎诊断的影响

目的通过患儿咽拭子及痰液标本肺炎支原体的培养,比较两种标本的培养结果及对儿童支原体肺炎诊断的影响。方法以2007年6月-2008年6月第四军医大学西京医院儿科住院的支气管肺炎患儿231例为研究对象;选取其中42例经ELISA法检测血清肺炎支原体阳性（急性期血清MP-IgM抗体滴度≥1：80[5]或恢复期血清MP-IgG有4倍升高）的患儿作为试验组,选取其中42例年龄及性别与试验组相匹配的ELISA法检测血清肺炎支原体抗体阴性（急性期血清MP-IgM及恢复期血清MP-IgG阴性）的患儿作为对照组,对两组患儿均同时进行咽拭子及痰液标本的肺炎支原体快速培养,并对两种标本的培养结果进行分析。结果试验组42例患儿中有26例痰液标本或咽拭子肺炎支原体快速培养阳性,阳性率61.9%（26/42例）。26例痰液标本或咽拭子肺炎支原体快速培养阳性的患儿中,18例患儿为痰液标本阳性,阳性率69.2%（18/26）,8例患儿为咽拭子标本阳性,阳性率30.8%（8/26）,其中7例患儿的痰液标本和咽拭子培养均阳性。对照组42例患儿中有1例咽拭子MP快速培养阳性。结论痰液标本MP快速培养的阳性率高于咽拭子培养的阳性率,与咽拭子相比,痰液标本是诊断支原体肺炎最佳的标本类型。对于ELISA法血清MP阳性的患儿,痰标本MP快速培养检测MP的临床意义远大于ELISA法血清MP阴性的患儿。

Comparison of mycoplasma culture for sputum and throat swab for diagnosis of mycoplasmal pneumonia in children

Objective To compare sputum and throat swab by mycoplasma culture for mycoplasma pneumoniae diagnosis in children.Metheds 42 children with serologically proven mycoplasma pneumoniae infection and 42 approximately matched mycoplasmal pneumonia seronegative controls was selected from 231 consecutively enrolled children hospitalized with clinically and radiologically confirmed pneumonia.Mycoplasma pneumoniae enzyme-linked immunosorbent assays （ELISA） was considered seropositive if the IgM in acute-phase serum was 1：80 or if there was 4-fold rise in IgG titer in convalescent-phase serum,otherwise ELISA was considered seronegative.84 cases were tested by throat swab and sputum mycoplasma culture and analyse the results of the culture.Results 26 of the 42 children diagnosed with mycoplasmal pneumonia by serum ELISA had positive mycoplasmal pneumonia culture from either throat swab or sputum.The 26 cases of positive mycoplasmal pneumonia culture was positive for 18 of sputum and 8 of throat swab （7 children had positive throat swab and sputum）.The positive rate was 69.2 % （18/26） for sputum while 30.8% （8/26） for throat swabs.One of the 42 control children with pneumonia had positive culture for mycoplasmal pneumonia from throat swab.Conclusion Sputum proved clearly to be the better respiratory specimens for diagnosis of mycoplasmal pneumonia.The detection of mycoplasmal pneumonia by culture was signi？cantly greater for children with positive mycoplasmal pneumonia ELISA than for children with negative ELISA.